Life Is Strange episode four spoilers: Going out on a wave or a rock

Episode four of Life Is Strange is now available, and if you've read our review you'll know we thought it wasn't just the best episode to date, but a sign that developer Dontnod is onto something truly special. That spoiler-free review of Dark Room begets this article filled near to the brim with them, so be warned... like this!

WARNING: Major spoilers for Life Is Strange – Episode Four 'Dark Room' follow.

The last time we saw Max Caulfield she was realising the true power within her, having altered the flow of history to save best friend Chloe's father. It was a choice of Max's, not the player's, that created a world in which Chloe is now severely disabled and, as we discover, dying.

Our time in this alternate reality is brief but powerful, further exploring the two character's friendship as Max internalises what has happened and wrestles with the guilt. It leads to the euthanasia scene that culminates with Max choosing whether to let Chloe drift away and die or betray her friend's wish.

It's the ultimate test of their friendship and exactly the kind of moral quandary that choice driven games like this should thrive on, as it certainly does here. It's a scene that could well end an entire episode but here it's a poignant reminder of the strength of Chloe and Max's bond – which is tested and strengthened further throughout the episode.

After this scene Max returns to her timeline via a heart-breaking scene in which she lets Chloe's dad leave and therefore die. It was inevitable that the game would return to its original setting, and it was a little surprising how brief our time in the alternate timeline was – but it all worked brilliantly.

Once back Max and Chloe continue their investigation, which leads to two of the series' best scenes to date. The first at Frank's trailer is entirely built-upon a number of the choices made in episodes one to three, and has three stark outcomes. Frank will either be killed by Chloe, injured by her or nobody will be hurt at all.

Who has the gun, whether Frank's dog was killed and whether Chloe stole the disability money all factor into the scene, but there's also a web of dialogue that keeps tensions on a knife-edge. There's a wonderful balancing act here, both from the developers and in terms of what Max has to do to try and keep everyone at bay.

This leads to the absolute best scene in the story so far as Max pieces together the evidence to find where Katie was taken after the Vortex Club party at which she was drugged. The player must connect the dots and whittle down the many pieces of evidence in a way that feels organic and more like an actual piece of detective work than anything Rocksteady attempted in their Batman series, or anything in the excellent Her Story for that matter.

I took notes, two pages of them, jotting down phone numbers, license plates, dates and times to pinpoint the location. There's one outcome from the scene, but how the player gets there is an exhilarating culmination of everything in the game so far and the first puzzle in the series that feels organic.

There is also a scene in episode four featuring Katie. Only players who talked her down at the end of episode two will be able to see the scene (those who didn't like me won't get anything in its stead). By all accounts it is a great scene providing a resolution for that arc. I look forward to seeing what that scene involves once it inevitably ends up on YouTube, but it's good to know there are whole scenes players can miss owing to certain choices.

Like episode three before it, it will be the ending people are talking about most. In the final moments of Dark Room we see Max drugged at the site where Rachel Amber's body was buried before her assailant shoots Chloe in the head. It turns out it was Mr Jefferson – Max's teacher and a character many had suspected.

His reveal as the killer - or rather a killer, we don't know yet if he killed Rachel, though it seems likely – wasn't exactly a huge shock. In the episode we discover Nathan Prescott really is a deranged young man, who we discover has been drugging women and photographing them in the titular dark room found beneath the barn Max and Chloe discover through their investigation.

Prescott is guilty of plenty, but it appears Jefferson has been working alongside him as part of a sick and twisted "working partnership". As we see in the disturbing post-credits tease, Jefferson has access to the dark room as well – confirming the connection, but how have the pair been operating? The assumption will be that Jefferson is the driving force, taking advantage of Nathan's issues and wealth.

The huge shock was the death of Chloe and Max's inability to rewind time and stop it. Does Jefferson know about her powers, or did he always intend to kill Chloe and kidnap Max. Chloe's death may well be undone eventually – like the death of her father once was, possibly via the selfie Warren took with Max outside the party – but first she needs to survive whatever Jefferson has in store.

The most disturbing part of episode four was undoubtedly the discovery of the dark room and its photos. That creepiness will pervade episode five's finale as the loose ends come together. How will Max escape, can she undo Chloe's death, will Jefferson and Nathan go after Rachel?

Oh, and how will that gargantuan storm play into everything? There's a lot left for Life Is Strange to do, but after episode four I'm more confident than ever in Dontnod's ability to see it through.

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